Insulated windows are assembled by spacing two layers of glass in a fixed relationship. The layers of glass are fixed together at the outer edges of the glass with a removable or permanent spacer plus a sealant, or a structure that contains both a sealant and spacer. The layers of glass are sealed together, forming a sandwich structure that contains the sealant and/or spacer between the glass layers. There is also a sealed air pocket between the two glass layers.
The formation of a window assembly requires multiple steps when a removable spacer is used. First, the spacer must be placed between the glass layers. Second, the sealant is injected at the edges of the glass. Third, the sealant is cured. Fourth, the spacer is removed. This process is labor intensive and requires expensive equipment.
In contrast, when a permanent spacer is used, an adhesive is applied to secure the permanent spacer between the two pieces of glass. The spacer is then set in place, followed by injection of a sealant between the spacer and the edges of the sheets of glass. This process is also labor intensive.
An alternative method of manufacturing insulated windows uses a unitary structure containing both a sealant and spacer. Sealant and spacer structures that are currently used are made of a flexible, hollow metal material which has a support structure that is folded over the two edges and one side of the hollow metal material, as in U.S. Pat. Nos. 4,431,691 and 8,230,661. This support structure has many disadvantages, including increased manufacturing costs for materials and labor. Additionally, the presence of a support structure makes the spacer rigid and hard to bend to allow a 90 degree angle to be formed at the corners of a window assembly.
FRP reinforcements offer a number of advantages such as corrosion resistance, non-magnetic properties, high tensile strength, lightweight and ease of handling.